US4528107A - Froth flotation - Google Patents
Froth flotation Download PDFInfo
- Publication number
- US4528107A US4528107A US06/517,656 US51765683A US4528107A US 4528107 A US4528107 A US 4528107A US 51765683 A US51765683 A US 51765683A US 4528107 A US4528107 A US 4528107A
- Authority
- US
- United States
- Prior art keywords
- froth
- froth flotation
- coal
- content
- solution
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000009291 froth flotation Methods 0.000 title claims abstract description 32
- 239000007788 liquid Substances 0.000 claims abstract description 20
- 229910052500 inorganic mineral Inorganic materials 0.000 claims abstract description 13
- 239000011707 mineral Substances 0.000 claims abstract description 13
- 239000003245 coal Substances 0.000 claims description 19
- 239000004215 Carbon black (E152) Substances 0.000 claims description 11
- 229930195733 hydrocarbon Natural products 0.000 claims description 11
- 150000002430 hydrocarbons Chemical class 0.000 claims description 11
- 150000001335 aliphatic alkanes Chemical class 0.000 claims description 9
- 238000000034 method Methods 0.000 claims description 9
- 125000003118 aryl group Chemical group 0.000 claims description 8
- 238000010248 power generation Methods 0.000 abstract 1
- 239000003921 oil Substances 0.000 description 12
- 239000007787 solid Substances 0.000 description 9
- 239000003849 aromatic solvent Substances 0.000 description 7
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 6
- 239000000203 mixture Substances 0.000 description 5
- 230000008901 benefit Effects 0.000 description 4
- 238000009835 boiling Methods 0.000 description 4
- 238000002485 combustion reaction Methods 0.000 description 4
- 239000007789 gas Substances 0.000 description 4
- 239000003250 coal slurry Substances 0.000 description 3
- 238000004821 distillation Methods 0.000 description 3
- 229920000151 polyglycol Polymers 0.000 description 3
- 239000010695 polyglycol Substances 0.000 description 3
- 239000000725 suspension Substances 0.000 description 3
- HYFLWBNQFMXCPA-UHFFFAOYSA-N 1-ethyl-2-methylbenzene Chemical class CCC1=CC=CC=C1C HYFLWBNQFMXCPA-UHFFFAOYSA-N 0.000 description 2
- UFWIBTONFRDIAS-UHFFFAOYSA-N Naphthalene Chemical compound C1=CC=CC2=CC=CC=C21 UFWIBTONFRDIAS-UHFFFAOYSA-N 0.000 description 2
- 150000004996 alkyl benzenes Chemical class 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 239000010779 crude oil Substances 0.000 description 2
- 239000003350 kerosene Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 150000005199 trimethylbenzenes Chemical class 0.000 description 2
- 239000011280 coal tar Substances 0.000 description 1
- 238000004939 coking Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 239000002283 diesel fuel Substances 0.000 description 1
- 238000005188 flotation Methods 0.000 description 1
- 239000000295 fuel oil Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000003498 natural gas condensate Substances 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 239000011368 organic material Substances 0.000 description 1
- 239000000454 talc Substances 0.000 description 1
- 229910052623 talc Inorganic materials 0.000 description 1
- 150000005201 tetramethylbenzenes Chemical class 0.000 description 1
- 238000005292 vacuum distillation Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D1/00—Flotation
- B03D1/02—Froth-flotation processes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D1/00—Flotation
- B03D1/001—Flotation agents
- B03D1/004—Organic compounds
- B03D1/006—Hydrocarbons
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D1/00—Flotation
- B03D1/001—Flotation agents
- B03D1/004—Organic compounds
- B03D1/008—Organic compounds containing oxygen
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D2201/00—Specified effects produced by the flotation agents
- B03D2201/02—Collectors
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D2201/00—Specified effects produced by the flotation agents
- B03D2201/04—Frothers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D2203/00—Specified materials treated by the flotation agents; Specified applications
- B03D2203/02—Ores
- B03D2203/04—Non-sulfide ores
- B03D2203/08—Coal ores, fly ash or soot
Definitions
- This invention concerns improvements in froth flotation, especially the froth flotation of coals for power stations, general steam raising and combustion.
- froth flotation is well known in the art, and is described in the literature, for example, "Handbook of Mineral Dressing", by A. F. Taggart, John Wiley & Sons, 1954, Section 12.
- froth floation is used to treat suspensions of coal fines which are difficult to treat in any other way.
- Conventional techniques involve the addition of a froth flotation oil to the suspension of the mineral and the passage of air through the suspension to create bubbles which carry the fine mineral to the surface to form a froth rick in minerals, the froth then being removed and the mineral recovered therefrom.
- the froth flotation oil may be a single compound or mixture of compounds of similar characteristics, but it is modern good practice, at least in the coal industry, to use a combination of a "frother" and a "collector".
- the "frothers” usable are of classes broadly known in the art, and the "collector” is usually a hydrocarbon oil of which distillate oils such as kerosene, industrial diesel fuel and furnace oil are the most widely used, especially kerosene.
- distillate oils such as kerosene, industrial diesel fuel and furnace oil are the most widely used, especially kerosene.
- certain residual oils namely a residual oil which is predominantly parafinnic and has a cut point of at least 190° C. at atmospheric pressure, is a useful collector for froth flotation.
- froth flotation In the production of coals for power stations, for general steam raising and industrial coals for combustion, the most important criteria in froth flotation are considered to be a high froth yield, together with a high ash-in-tailings.
- the froth yield is the weight percentage of solids in the dried froth against the solids content of the initial charge of coal slurry
- the ash-in-tailings is the weight percentage of ash (mineral matter remaining after combustions) in the solids residue from the froth flotation cell, on a dry basis. Since the recovered fine coal from the flotation cells is going to combustion, clearly high yield are important as well as minimising the ash content by maximising the ash rejected from the cells (ash in tailings).
- the present invention therefore provides the use of a liquid having an aromatic content greater than 21% or a naphthenic content greater than 41%, by weight, as a collector in the froth flotation of minerals.
- the invention also provides a froth flotation mixture comprising the defined liquid in association with a "frother".
- the invention further provides a method of treating minerals in a froth flotation cell comprising the operation of the cell using a collector which is the defined liquid.
- the liquid has a total content of aromatics and naphthenes greater than 62% by wt; the aromatic content is preferably in the range 21 to 31% by wt.
- the remainder of the liquid is suitably made up of alkanes, e.g., a mixture of n- and branched-alkanes, but may be any organic material which does not interfere with the effectiveness of the collector in use.
- the alkane content of the preferred liquid is less than 56%, more preferably less than 38%.
- Liquids suitable for use in the invention may be obtained from a wide variety of sources provided that the component requirements are met.
- the liquid may be a distillate boiling in the range 80° to 350° C., preferably 150° to 250° C., a residue such as the residue from the distillation of gas condensate, or from a second distillation of crude oil, an oil produced by the vacuum distillation of crude oil or a neutral hydrocarbon fraction produced from coal tar, and combinations of these materials or blends thereof with other hydrocarbon materials to give the required component content.
- a residue such as the residue from the distillation of gas condensate
- a second distillation of crude oil an oil produced by the vacuum distillation of crude oil or a neutral hydrocarbon fraction produced from coal tar, and combinations of these materials or blends thereof with other hydrocarbon materials to give the required component content.
- One such collector is the condensate resulting from the distillation of North Sea gas condensate blended with an aromatic solvent.
- the collector of the invention is used in conventional manner with a "frother".
- a preferred “frother” is a polyglycol ether, and these are commercially available; other conventional “frothers” may, however, be used.
- the "frother” is suitably used with the collector in an amount of up to 40% by weight, suitably 10 to 20% by weight, especially about 15% by weight.
- the collector and frother may be combined before use and supplied to the froth flotation cell as a mixture, but they may be fed separately to the cell if desired.
- the invention offers particular advantages over other collectors in the treatment of coals for power stations, but the invention may be used also in the treatment of other coals or other minerals which require an oily collector, such as talc or illmonite.
- oily collector such as talc or illmonite.
- Froth flotation solution A A commercially available froth flotation solution recommended for use for steam coal treatment, containing about 15% by weight of a standard commercial polyglycol ether "frother" together with a hydrocarbon liquid collector.
- the hydrocarbon liquid was analysed to contain 26.5% by weight naphthanes, 20% aromatics and 53.5% n- and branched-chain alkanes.
- the aromatic content of this collector is less than 21% and the naphthenes content is less than 41% so that the hydrocarbon liquid does not fall within the present invention but gives a good comparison.
- Froth flotation solution B A solution was made up containing 15% of the same "frother" as in solution A, together with 68% of a residual oil obtained by distilling off components boiling up to 190° C. from a North Sea natural gas condensate and 17% of a completely aromatic solvent. The residual oil and the solvent, together forming a liquid collector according to the invention were analysed to give a total naphthene content of 21%, a total aromatic content of 23.5% and the remainder being n- and branched-chain alkanes.
- the aromatic solvent was a commercial aromatic solvent boiling over the range 170° to 250° C. and containing alkyl benzenes, mainly tri-methyl benzenes and ethyl methyl benzenes.
- the froth flotation solutions A and B were tested in a laboratory froth flotation cell with coal feed from the National Coal Board's Bilthorpe Colliery coal preparation plant. The coal from the plant is sold to power stations. Tests were carried out at a number of dose rates ranging from 0.25 to 1 liter of solution per tonne of coal (on a dry basis), which is charged to the cell in the form of a slurry containing nominally 10% solids.
- froth yield that is the percentage of dried froth against solids content of the initial charge of coal slurry, against dosage rate of the froth flotation solution. The results were plotted on the graph of FIG. 1 and a curve drawn by computer. It can be seen that froth yields for solution B, according to the invention, were about 8 percentage points greater than for the conventional commercial solution, over the whole range tested.
- the ash-in-tailings that is the percentage ash in the solids residue from the froth flotation cell, was also plotted against dosage rate and curves drawn by computer and is shown in FIG. 2. Over the range tested, the solution B gave an average 4 to 5 percentage points improvement over the conventional commercial solution.
- Froth flotation solution C A commercially available froth flotation solution recommended for use for steam coal treatment, containing about 20% by weight of a standard commercial polyglycol ether "frother" together with a hydrocarbon liquid collector.
- the hydrocarbon liquid was analysed to contain 40.1% by weight naphthenes, 13.1% aromatics and 46.8% n- and branched-chain alkanes.
- the aromatic content of this collector is less than 21% and the naphthenes content is less than 41% so that the hydrocarbon liquid does not fall within the present invention but gives a good comparison.
- Froth flotation solution D A solution was made up containing 20% of the same "frother" as in solution C, together with 60% of a conventional Gas Oil and 20% of a completely aromatic solvent.
- the Gas Oil and the solvent, together forming a liquid collector according to the invention were analysed to give a total naphthene content of 24.5%, a total aromatic content of 33.25% and the remainder being n- and branched-chain alkanes.
- the aromatic solvent was a commercial aromatic solvent boiling over the range 170° to 250° C. and containing alkyl benzenes, mainly tri- and tetra-methyl benzenes and ethyl methyl benzenes.
- the froth flotation solutions C and D were tested in a laboratory froth flotation cell with coal feed from the National Coal Board's Dodworth Colliery coal preparation plant. The coal from this plant is sold to power stations. Tests were carried out at a number of dose rates ranging from 0.25 to 1 liter of solution per tonne of coal (on a dry basis), which is charged to the cell in the form of a slurry containing nominally 10% solids.
- froth yield that is the percentage of dried froth against solids content of the initial charge of coal slurry, against dosage rate of the froth flotation solution. The results were plotted on the graph of FIG. 3 and a curve drawn by computer. It can be seen that froth yields for solution D, according to the invention, were about 1.8 to 0.5 percentage points greater than for the conventional commercial solution, over the whole range tested.
- the present invention provides economically significant improvements in the froth flotation treatment of power station coals compared to a good commercial froth flotation solution.
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Abstract
Description
Claims (7)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8222408 | 1982-08-03 | ||
| GB8222408 | 1982-08-03 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US4528107A true US4528107A (en) | 1985-07-09 |
Family
ID=10532087
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US06/517,656 Expired - Lifetime US4528107A (en) | 1982-08-03 | 1983-07-27 | Froth flotation |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US4528107A (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5379902A (en) * | 1993-11-09 | 1995-01-10 | The United States Of America As Represented By The United States Department Of Energy | Method for simultaneous use of a single additive for coal flotation, dewatering, and reconstitution |
| WO2006086443A3 (en) * | 2005-02-08 | 2007-03-29 | Sasol North America Inc | Process and composition for froth flotation |
| US20080179570A1 (en) * | 2007-01-31 | 2008-07-31 | Georgia-Pacific Chemicals Llc | Maleated and oxidized fatty acids |
| US20090178959A1 (en) * | 2008-01-15 | 2009-07-16 | Georgia-Pacific Chemicals Llc | Method for the beneficiation of coal |
| US20090194731A1 (en) * | 2008-01-31 | 2009-08-06 | Georgia-Pacific Chemicals Llc | Oxidized and maleated derivative compositions |
| US20090243373A1 (en) * | 2008-03-25 | 2009-10-01 | International Truck Intellectual Property Company, Llc | Drive away axle assembly |
| US8875898B2 (en) | 2008-02-05 | 2014-11-04 | Georgia-Pacific Chemicals Llc | Method for the froth flotation of coal |
| CN108940602A (en) * | 2018-08-21 | 2018-12-07 | 中国矿业大学 | Collecting agent and method for floating for weakly caking coal coal slime flotation |
| CN109127148A (en) * | 2018-08-21 | 2019-01-04 | 中国矿业大学 | Jet coal coal slime flotation collector and preparation method, jet coal coal slime flotation method |
| WO2020178262A1 (en) | 2019-03-05 | 2020-09-10 | Basf Se | Mixture of octene hydroformylation by-product and diesel, kereosene or c8-c20 olefines as collectors |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB207977A (en) * | 1922-11-13 | 1923-12-13 | Luckenbach Processes Inc | Process of concentrating ores |
| GB953550A (en) * | 1959-08-11 | 1964-03-25 | Prod Chim D Auby Soc D | Materials for the treatment of solid particles, and their use |
| GB1360031A (en) * | 1970-06-24 | 1974-07-17 | Wanzenberg F W | Metal recovery method |
| GB2029274A (en) * | 1978-08-04 | 1980-03-19 | Ici Ltd | Recovery of metal concentrates from mineral ores |
| GB2111866A (en) * | 1981-12-18 | 1983-07-13 | Coal Ind | Improvements in froth flotation |
| US4416769A (en) * | 1981-12-24 | 1983-11-22 | Coal Industry (Patents) Limited | Froth flotation |
-
1983
- 1983-07-27 US US06/517,656 patent/US4528107A/en not_active Expired - Lifetime
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB207977A (en) * | 1922-11-13 | 1923-12-13 | Luckenbach Processes Inc | Process of concentrating ores |
| GB953550A (en) * | 1959-08-11 | 1964-03-25 | Prod Chim D Auby Soc D | Materials for the treatment of solid particles, and their use |
| GB1360031A (en) * | 1970-06-24 | 1974-07-17 | Wanzenberg F W | Metal recovery method |
| GB2029274A (en) * | 1978-08-04 | 1980-03-19 | Ici Ltd | Recovery of metal concentrates from mineral ores |
| GB2111866A (en) * | 1981-12-18 | 1983-07-13 | Coal Ind | Improvements in froth flotation |
| US4416769A (en) * | 1981-12-24 | 1983-11-22 | Coal Industry (Patents) Limited | Froth flotation |
Cited By (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5379902A (en) * | 1993-11-09 | 1995-01-10 | The United States Of America As Represented By The United States Department Of Energy | Method for simultaneous use of a single additive for coal flotation, dewatering, and reconstitution |
| US8136669B2 (en) | 2005-02-08 | 2012-03-20 | Filler Paul A | Process and composition for froth flotation |
| WO2006086443A3 (en) * | 2005-02-08 | 2007-03-29 | Sasol North America Inc | Process and composition for froth flotation |
| US8257608B2 (en) * | 2005-02-08 | 2012-09-04 | Filler Paul A | Process and composition for froth flotation |
| US20090301941A1 (en) * | 2005-02-08 | 2009-12-10 | Paul A Filler | Process and composition for froth flotation |
| US20120132571A1 (en) * | 2005-02-08 | 2012-05-31 | Filler Paul A | Process and Composition for Froth Flotation |
| US20120132844A1 (en) * | 2005-02-08 | 2012-05-31 | Filler Paul A | Process and Composition for Froth Flotation |
| US20080179570A1 (en) * | 2007-01-31 | 2008-07-31 | Georgia-Pacific Chemicals Llc | Maleated and oxidized fatty acids |
| US8334363B2 (en) | 2007-01-31 | 2012-12-18 | Georgia-Pacific Chemicals Llc | Oxidized and maleated compounds and compositions |
| US8071715B2 (en) | 2007-01-31 | 2011-12-06 | Georgia-Pacific Chemicals Llc | Maleated and oxidized fatty acids |
| US20090178959A1 (en) * | 2008-01-15 | 2009-07-16 | Georgia-Pacific Chemicals Llc | Method for the beneficiation of coal |
| US8925729B2 (en) | 2008-01-15 | 2015-01-06 | Georgia-Pacific Chemicals Llc | Method for the beneficiation of coal |
| US10307770B2 (en) | 2008-01-15 | 2019-06-04 | Ingevity South Carolina, Llc | Method for the benificiation of coal |
| US8133970B2 (en) | 2008-01-31 | 2012-03-13 | Georgia-Pacific Chemicals Llc | Oxidized and maleated derivative compositions |
| US20090194731A1 (en) * | 2008-01-31 | 2009-08-06 | Georgia-Pacific Chemicals Llc | Oxidized and maleated derivative compositions |
| US8875898B2 (en) | 2008-02-05 | 2014-11-04 | Georgia-Pacific Chemicals Llc | Method for the froth flotation of coal |
| US7641289B2 (en) * | 2008-03-25 | 2010-01-05 | International Truck Intellectual Property Company, Llc | Drive away axle assembly |
| US20090243373A1 (en) * | 2008-03-25 | 2009-10-01 | International Truck Intellectual Property Company, Llc | Drive away axle assembly |
| CN108940602A (en) * | 2018-08-21 | 2018-12-07 | 中国矿业大学 | Collecting agent and method for floating for weakly caking coal coal slime flotation |
| CN109127148A (en) * | 2018-08-21 | 2019-01-04 | 中国矿业大学 | Jet coal coal slime flotation collector and preparation method, jet coal coal slime flotation method |
| CN108940602B (en) * | 2018-08-21 | 2020-04-24 | 中国矿业大学 | Collecting agent for flotation of weakly sticky coal slime and flotation method |
| WO2020178262A1 (en) | 2019-03-05 | 2020-09-10 | Basf Se | Mixture of octene hydroformylation by-product and diesel, kereosene or c8-c20 olefines as collectors |
| US12246332B2 (en) | 2019-03-05 | 2025-03-11 | Basf Se | Mixture of octene hydroformylation by-product and diesel, kerosene or C8-C20 olefins as collectors |
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Legal Events
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|---|---|---|---|
| AS | Assignment |
Owner name: COAL INDUSTRY (PATENTS) LIMITED; HOBART HOUSE, GRO Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:MCCAFFREY, DAVID J. A.;SHEPPARD, JOHN P.;REEL/FRAME:004158/0545 Effective date: 19830721 Owner name: COAL INDUSTRY (PATENTS) LIMITED, ENGLAND Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:MCCAFFREY, DAVID J. A.;SHEPPARD, JOHN P.;REEL/FRAME:004158/0545 Effective date: 19830721 |
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